Effect of Varying Irrigation Regimes and Cultivars on Growth, Yield, Water Use Efficiency and Economics of Rice (Oryza sativa) under Aerobic Condition

Abstract

The present study was undertaken for standardization of irrigation interval and performances of medium duration selected rice varieties under the aerobic conditions in the westen Odisha. The field experiment was conducted at the Regional Research Technology and Transfer Station (RRTTS), Chiplima, Sambalpur, Odisha, during the summer season of 2019 and 2020 to see the performance of medium-duration rice varieties with varying irrigation regimes under aerobic conditions. The experiment was laid out in split plot design with three replications and consisted of four irrigation regimes (I1 = Irrigation at IW/CPE = 1.0, I2 = Irrigation at IW/CPE = 1.5, I3 = Irrigation at IW/CPE = 2.0, and I4 = Irrigation at IW/CPE = 2.5) in main plot treatments and four varieties     (V1 = Naveen, V2 = MTU-1010, V3= CR Dhan-201 and V4 = CR Dhan-204 in subplot treatments. The result of the pooled mean of both years showed that growth and yield attributes significantly affect in regards to different irrigation regimes and cultivars. The maximum plant height (69.0 cm) and filled grains per panicle (80.98) leaf area index (LAI ) at 75DAS (3.940, dry matter accumulation of the shoot at 90 DAS ( 927 g m-2), number of effective panicles m-2 (287)  and test weight (22.27 g) was maximum at irrigation regime IW/CPE = 2.5. In contrast, it was at par with the irrigation regime at IW/CPE = 2.0. The maximum plant height(67.1cm), filled grains per panicle (74.47), leaf area index (LAI ) at 75DAS (3.52), dry matter accumulation of the shoot at 90 DAS (901 g m-2 ), and a number of effective panicles m-2 (286)  were recorded with CR Dhan 201  which was significantly higher as compared to other cultivars. The result of the pooled mean of both years showed that the highest grain yield was recorded at IW/CPE = 2.5, i.e., 4.07 t/ha, which was at par with IW/CPE = 2.0 (3.90 t/ha) and significantly superior to rest of other irrigation regimes. But in the case of cultivars, the highest grain yield was obtained with variety CR-Dhan 201 (3.54 t/ha), which was at par with variety Naveen (3.30t/ha) and significantly superior to the rest of other cultivars. The highest mean FWUE of 40.71kg/ ha-cm was observed with irrigation at IW/CPE 1.5, which was at par with other irrigation regimes except IW/CPE 2.5, whereas the highest B: C ratio (1.74)  was observed with irrigation at IW,/CPE 2.0 which was at par with  IW/CPE 2.5 (1.73) and significantly superior to other irrigation regimes. But in the case of cultivars, the highest mean FWUE of 41.60kg/ ha-cm and B: C ratio (1.62) was observed with variety CR Dhan 201 and significantly superior to the rest of the other cultivars. Hence, a variety like CR Dhan 201 needs to be irrigated at IW/CPE 2.0 to produce economically optimum yield and field water use efficiency on sandy loam soils of the western region of Odisha under aerobic conditions.